Is this mould?

Four questions. You do not need to photograph anything and you do not need an account — you are probably holding the jar.

Not mould. It is hungry.

Nail polish remover is acetone, and vinegar is acetic acid; your starter makes both once the food is gone. It smells worse than it is.

What you do now

  1. 1 Feed 1:2:2 and put it somewhere between 22 and 24 degrees.
  2. 2 Feed again after twelve hours, even if it did not rise.
  3. 3 Move to feeding 1:5:5 daily after that.
Do the starter check Read why mould goes deeper than you can see Start over